Versatile Reaction Pathways of 1,1,3,3,3-Pentafluoropropene at Rh(I) Complexes [Rh(E)(PEt3)3] (E=H, GePh3, Si(OEt)3, F, Cl): C-F versus C-H Bond Activation Steps

Abstract

The reaction of the rhodium(I) complexes [Rh(E)(PEt3)3] (E=GePh3 (1), H (6), F (7)) with 1,1,3,3,3-pentafluoropropene afforded the defluorinative germylation products Z/E-2-(triphenylgermyl)-1,3,3,3-tetrafluoropropene and the fluorido complex [Rh(F)(CF3CHCF2)(PEt3)2] (2) together with the fluorophosphorane E-(CF3)CH=CF(PFEt3). For [Rh(Si(OEt)3)(PEt3)3] (4) the coordination of the fluoroolefin was found to give [Rh{Si(OEt)3}(CF3CHCF2)(PEt3)2] (5). Two equivalents of complex 2 reacted further by C−F bond oxidative addition to yield [Rh(CF=CHCF3)(PEt3)2(μ-F)3Rh(CF3CHCF2)(PEt3)] (9). The role of the fluorido ligand on the reactivity of complex 2 was assessed by comparison with the analogous chlorido complex. The use of complexes 1, 4 and 6 as catalysts for the derivatization of 1,1,3,3,3-pentafluoropropene provided products, which were generated by hydrodefluorination, hydrometallation and germylation reactions.